This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Brazzein is a sweet protein found in South American fruit plant Pentadiplatra brazzeana Baillon. The protein interacts with the sweet receptor T1R2-T1R3. To understand their biological significance and interaction with the sweet receptor, we need to understand the structures of sweet brazzein and the non-sweet mutants. This gives insight into their function and help understand interaction with the receptor.